Priest OOM Fast :(

[crowdx]

Hi all,
so I am leveling a new team comprised of a druid tank, holy priest and 3 shammies (really the stereotypical group). My issue is the couple of times I have tried dungeons it seems that the priest jsut runs out of mana so fast. My priest is called Desiresend and is on US Uther and she is dual specced Holy/Disc . My shammies put down mana totems, and she buffs with I think she should be doing a lot better that she is and so I am really confused as to what I am missing with this priest.
I am coming from a druid healing so REALLY a noob with the priest, should I be macroing any spells with my dps spam?
HELP!!!
EDIT: Oh btw I use ISBoxer with Click Regions and Vuhdo